Factor of safety for Hoist Bracket 9

[kaffy]

Good Morning fellow engineers,

I am working on a hoist bracket. The hoist bracket will be attached to ceiling (Structural slab) by Hilti kwik bolts. 2 tonne load will be attached to hoist bracket with a chain block.I am not sure what is the minimum factor of safety I need for the hoist bracket. I checked the worksafe but couldn't find anything for hoist bracket. Factor of safety for ropes chains are mentioned there but not the hoist bracket or anything above the hook. Any help will be appreciated.

Thank You

 

[r13]

If in the US, maybe you shall check ASME B30.16 - Overhead Underhung and Stationary Hoists, or ASME B30.26 - Rigging Hardware.

 

[miningman]

What are the consequences of failure??? Answer that , and it should give you an idea of the required FOS

 

[desertfox]

Hi Kaffy

I went on this site and found FOS for various industrial stuff, for lifting hooks it recommends a FOS of 8-9 why not use that figure?

https://www.engineeringtoolbox.com/factors-safety-fos-d_1624.html

“Do not worry about your problems with mathematics, I assure you mine are far greater.” Albert Einstein

 

[r13]

Also note, if not prohibited, it is not recommended to use post installed anchor for overhead hanging/lifting devices. There are too many catastrophic failure cases. Use through rod, or embedment in the concrete floor.

 

[dik]

For some mining stuff, in Canada, a FOS of 5 minimum is required while if lifting over the shaft, a FOS of 10 minimum is required. For anything that is 'mission critical' I would only use adhesive anchors... I would not use Kwik bolts...just a personal quirk...

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

[STrctPono]

If you look at a lot of companies that design devices for handling of precast concrete elements, their lifting devices are typically designed with a factor or safety of 4:1 or 5:1. You might also want to look at OSHA Act part 1910.

 

[PEinc]

Safety Factors per

https://www.engineeringtoolbox.com/factors-safety-fos-d_1624.html

Structural steel work in buildings 4 - 6
Structural steel work in bridges 5 - 7

WOW!

http://www.PeirceEngineering.com

 

[kaffy]

@All Due to cost implications, I was looking for the minimum factor of safety I need. It seems most references are okay with 4 and since it is for short duration, I will use 4 in my case.
Thank you very much for valuable responses.

 

[miningman]

Sure hope the consequences of a failure are not fatalities!!!!!!!!!!!

 

[EdStainless]

I have always used used 4 if it was not possible for a person to ever be under the hook and it was short term.
If a person could get under the hook or we were leaving it in place (for unknown future use) we used 8.
No discussion.

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P.E. Metallurgy, consulting work welcomed

 

[dik]

Depends on the work and/or jurisdiction... under the Mines Act, in Canada, your FOS is either 5 or 10... as far as buildings go... I typically use a LL factor of 1.5 and have used this for numerous hoists, etc. where there are no other requirements.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik